This research is designed to define the effects of a maternal protein-deficient diet during gestation on hypothalamic, pituitary and thyroid function in the dam. It is also intended to elucidate the effects of maternal protein deprivation on morphogenesis of the fetal neonatal and postnatal hypothalamus and pituitary and the secretory activity of the hypothalamus, pituitary and thyroid. The effects of postnatal diet will also be examined. BIBLIOGRAPHIC REFERENCES: Hastings-Roberts, M.M. and Zeman, F.J. 1976 The effect of maternal protein deprivation on placental and fetal development. Fed. Proc. 35:422 (abstract). Shrader, R.E., Hoernicke, C.A., Parker, H.R. and Zeman, F.J. 1976 Thyroidal iodine uptake and endocytic response to exogenous TRH and TSH in progeny of protein-deprived rats. Fed. Proc. 35:421 (abstract).